Add SSRF parser and redirect revalidation gates

[cuph7022]

Summary

• Add focused SSRF evidence gates for parser consistency, redirect revalidation, DNS/final IP validation, alternate IP encodings, cloud metadata endpoints, and protocol changes.
• Add SCR-SSRF finding IDs mapped to CWE-918.
• Extend the output template with an SSRF URL fetch review matrix.
• Bump secure-code-review to version 1.1.0.

Closes #1702

Validation

• Reviewed the generated single-file Markdown change.
• Confirmed the updated skill includes version: "1.1.0" and SCR-SSRF-01 through SCR-SSRF-06.
• Did not clone, install dependencies, or run project code.